limit number of cores used by next build

[aryankarim]

Summary

Hello fellas,

I wanted to know if I could limit the number of physical CPU cores used by the next build command. I've looked at next and swc documentation, but there is no mention of this matter.

Anyone has managed to do this?

Additional information

No response

Example

No response

[icyJoseph]

IIRC, you can use experimental.cpus in next.config.js:

• https://github.com/vercel/next.js/blob/canary/packages/next/src/server/config-shared.ts#L241

[aryankarim]

I've 16 cores. I supplied 1 cpu like so, but weirdly 6 cores are heavily used for the build. Once I made it 16, all 16 threads were being used.

Am I correct or the margins are unnoticeable and these variables have no effect?

1 cpu

experimental: {
  workerThreads: false,
  cpus: 1,
},

16 cpu

experimental: {
  workerThreads: false,
  cpus: 16,
},